1. Field of the Invention
The invention relates generally to resistors within semiconductor structures. More particularly, the invention relates to polysilicon containing resistors within semiconductor structures.
2. Description of the Related Art
In addition to transistors, diodes and capacitors, semiconductor structures and semiconductor circuits routinely also incorporate resistors. Resistors may be used within semiconductor circuits as signal processing components and power dissipative components, as well as resistive load components.
Although resistors are common components within semiconductor circuits, resistors, like other semiconductor circuit components, are desirably fabricated with enhanced performance at decreased dimensions. Within the context of resistor fabrication, enhanced performance is often manifested within the context of a bulk resistivity precision or a sheet resistance precision of a resistor, since bulk resistivity precision or sheet resistance precision is often of importance to circuit performance.
Resistors within semiconductor circuits may be fabricated using any of several resistive materials. However, a particularly common resistive material is a polysilicon containing resistive material. Polysilicon containing resistive materials may be fabricated with different bulk resistivities or sheet resistances, while incorporating different levels and types of dopants. The dopants may be intrinsically incorporated when depositing a polysilicon material. In the alternative, such dopants are commonly ion implanted when forming polysilicon resistors.
Various methods have been disclosed in the semiconductor fabrication art for forming polysilicon resistors.
For example, Lee, in U.S. Pat. No. 4,489,104 teaches a polysilicon resistor that may be formed using a sequential co-doping method. Within this prior art reference, the polysilicon resistor that is formed using the sequential co-doping method has an inhibited lateral diffusion.
In addition, Chen et al., in U.S. Pat. No. 6,242,314, teaches a concurrent co-doping method that may be used to form a polysilicon resistor. Within this prior art reference, the polysilicon resistor that is formed using the concurrent co-doping method may be used as a temperature controller.
As semiconductor technology continues to advance and semiconductor device dimensions continue to decrease, needs continue to exist for fabricating semiconductor devices, such as polysilicon containing resistors, with enhanced performance. In particular, needs continue to exist for fabricating polysilicon containing resistors with enhanced resistivity precision or sheet resistance precision.